The median cost of residential solar power in the US reached $4.10 per watt in 2015, down from roughly $7 per watt in 2010. That’s according to the latest figures from the Lawrence Berkeley National Laboratory (Berkeley Lab) Tracking the Sun IX, which showed that residential solar prices fell 20 cents per watt or 5 percent from 2014.
That’s just one of the two annual reports that Berkeley introduced today (Aug. 24). The other was the Utility-Scale Solar 2015 report. That report found that costs for utility scale solar fell 30 cents per watt in 2015 or 12 from 2014. The lab also stated that early data from 2016 suggests that prices are continuing to fall this year.
“This marked the sixth consecutive year of significant price reductions for distributed PV systems in the US,” stated Galen Barbose lead author of Tracking the Sun and a researcher at Berkeley Lab’s Electricity Markets and Policy Group.
The report found that the price declines came largely from reductions in hardware and soft costs rather than solar panel prices. The reports noted that the cost of solar panels have been relatively the same since 2012.
While the media price has continued to drop the reports also showed that there’s a tremendous variability in pricing that continues. “For example, among residential systems installed in 2015, 20 percent sold for less than $3.30 per watt, while another 20 percent sold for more than $5.00 per watt,” the lab observed. Utility-scale solar projects saw similar variability with the cheapest 20 percent coming in below $1.60 per watt and the most expensive 20 percent coming in above $2.60 per watt.
“This variability reflects a host of factors: differences in system design and component selection, market and regulatory conditions, and installer characteristics, to name a few,” said Berkeley Lab’s Naïm Darghouth.
“Some of the observed price differences between projects can be explained by varying lag times between contract negotiation and project completion, as some of these projects have been under development, or even construction, for several years,” added Berkeley Lab’s Joachim Seel.
The economics of solar power continue to improve, according to the reports. When added to the extension of the 30 percent investment tax credit (ITC) through 2019, it’s expected that solar will continue to expand in all its market segments over the next few years, the lab said.Tweet